Silkie
The silkie guinea pig is the North American name for the smooth longhair called sheltie in Britain and Europe. The mane and face hair flow backward, leaving the face visible, while the coat extends around the sides and across the hindquarters. It lacks the forward frontal and rump rosettes that characterize a Peruvian. Silkie is recognized in ARBA's Standard of Perfection for 2026 to 2030. Its British counterpart has a British Cavy Council Full Standard under the Sheltie name; the current standard was updated in 2024.
The European standard also lists Sheltie. British guidance permits any color or mixture of colors and emphasizes texture, density and a full, unparted mane. Daily grooming keeps the long coat clean and free of tangles, with the mane and face hair presented in their natural rearward direction. Silkie Satin is a separate recognized ARBA breed with satin sheen. Silkie and sheltie are regional names for the same breed rather than different coat types.